Could be. I'll have to look deeper when I have more time, but I did see the Phillies rank 16th this year in average runs per game at 4.25; last year they were 5th with 5.10. Obviously, scoring less runs opens the possibility of leads being lost despite the collective BP ERA having improved.
There are other factors that could have a play as well. Suarez/Falter have done very well as the BP arm of the tandem starts this season, e.g. Then there's the ever-present Phillies Phrustration Phactor: here, it being games where the bats have taken the day off or the Phils are getting blown out early - and the BP proceeds to toss six scoreless innings like it's standard routine.
